1. Field of the Invention
The present invention relates to a drive circuit of an electrostrictive element actuator, and a diesel engine fuel injection device having such a circuit. The drive circuit according to the present invention is arranged in a fuel injection device of a diesel engine, and is used for an actuator which realizes an effective pilot injection so as to reduce idling noise. Note that an electrostrictive element actuator device and a fuel injection device using the same are described in Igashira et al U.S. Ser. No. 754,750 (filed on July 15, 1985) by the same assignee as of the present invention.
2. Description of the Related Arts
Pilot injection is known to be effective in reducing the idling noise of a diesel engine. To realize this, an actuator comprising an electrostrictive element, for example a PZT, and a drive circuit thereof are also known. However, the drive circuit comprises a plurality of expensive switching elements, for example SCRs, pulse transformers, and coil cores. For this reason, it has been difficult to realize an inexpensive drive circuit having reliable operation characteristics.